Hy-Brazil is a phantom island which features in many Irish myths. It was said to be cloaked in mist, except for one day each seven years, when it became visible but could still not be reached.

Expeditions left Bristol in 1480 and 1481 to search for it, and a letter written shortly after the return of John Cabot from his expedition in 1497 reports that land found by Cabot had been "discovered in the past by the men from Bristol who found Brasil".

Others claimed to have seen the island, or even landed on it, the last supposed sighting being in 1872. Roderick O’Flaherty in A Chorographical Description of West or H-Iar Connaught (1684) tells us "There is now living, Morogh O'Ley, who immagins he was himself personally on O'Brasil for two days, and saw out of it the iles of Aran, Golamhead, Irrosbeghill, and other places of the west continent he was acquainted with."

On maps, the island was shown as being circular, soon with a central strait or river running east-west across its diameter. Despite the failure of attempts to find it, it appeared regularly on maps lying south west of Galway Bay from 1325 until 1865, by which time it was called Brazil Rock.

Category:Phantom islands